Every one of the plumbers has the ability and experience to complete this job.

The prepositional phrase “of the plumbers” is not the subject; it is modifying (giving more information about) the subject. “Every one” is the subject.

If you take away the prepositional phrase, you are left with:

Every one… (“has” or “have”) the ability and experience….

“One” is singular, so the correct verb is the singular verb “has.”

The crew is helping to develop advanced supply chain processes.

In this sentence, the crew is doing the action, so it is the subject. Even though it is made up of many people, the crew is a single unit, so it is singular. It requires the singular verb “is.”

Those scissors are not sharp enough to cut the aluminum.

Many tools that have two primary parts, such as scissors, pliers, shears, tweezers, etc., are plural. In this example, the plural subject (“scissors”) requires a plural verb (“are”).

The crane operator and the lineman navigate using the new GPS system.

There are two subjects in this sentence (crane operator and lineman), so the subject is plural. The plural subject must be paired with the plural verb “navigate.” (Tip: When you have two subjects, replace them with the word “we” to make it easier to select the correct verb. For example, in this sentence, you can replace “The crane operator and the lineman” with “They” to form the sentence “They navigate …”)

Mr. Jones or his assistants run the meeting.

The word “or” separates the subjects “Mr. Jones” and “assistants.” When two or more subjects are separated, focus on the subject closest to the verb. In this example, the subject closest to the verb is “assistants.” Because “assistants” is plural, it requires the plural verb “run.”

Neither the generator nor the instruments appear to be working.

The word “nor” separates the subjects “generator” and “instruments.” When two or more subjects are separated, focus on the subject closest to the verb. In this example, the subject closest to the verb is “instruments.” Because it is plural, it requires the plural verb “appear.” (Tip: When two or more subjects are separated, try reading the sentence using only the subject closest to the verb. In this example, the sentence would read: “The instruments appear…”)

All employees, other than the retiring president, are planning to attend the annual company picnic.

In this sentence, “all employees” are doing the action (planning), so the subject is plural. The phrase “other than the retiring president” is not part of the subject; it simply adds extra information about the subject. 

Tip: When you see a phrase set off by commas, try reading the sentence without the words between the commas. In this example, the sentence would read: All employees … (“is” or “are”) planning to attend the annual company picnic.

The number of necessary engines decreases with the size and weight of the airplane.

“The number” refers to a specific number, even if the sentence does not tell us what that number is. Because the number is specific, the subject is singular and requires the singular verb “decreases.” The  phrase “of necessary engines” is a prepositional phrase that modifies (gives more information about) the subject, but it is not part of the subject. 

Tip: Try removing the prepositional phrase and adding an actual number after the words “the number.” In this example, the sentence could read: The number twelve (“decreases” or “decrease”) with the size…

A number of heavy equipment operators have volunteered to train the new recruits.

In this example, “a number” is not specific. It means “many” or “several,” so the subject is plural and requires the plural verb “have.” The phrase “of heavy equipment operators” is a prepositional phrase that modifies the subject, but it is not part of the subject. 

Tip: Try removing the prepositional phrase and using “Many” or “Several” instead of “A number.” In this example, the sentence would read: Many (“has” or “have”) volunteered to train…